A folded cascode amplifier circuit is widely used as a one-stage amplifier with high gain and high speed, and is a one-stage amplifier. However, has a pole of frequency-gain/phase characteristics in the vicinity of folded nodes X and Y and an output node and has a high gain. Because of this, if it is used with negative feedback being set and the load of feedback is small, the phase margin runs short and there is a possibility that oscillation occurs.
Consequently, measures to prevent oscillation have been proposed, however, there have been such problems that a capacitor with a large area in LSI, that power increases, is provided, etc.